矮秆基因对小麦部分农艺性状的效应

以中国主要麦区的124份小麦品种为材料,利用分子标记和系谱分析相结合,对其按照所含的矮秆基因Rht-B1b、Rht-D1b和Rht8进行分类,结合田间株高、旗叶长、小穗数和穗粒数以及室内苗期根系长度等农艺形状的调查,分析不同矮秆基因对小麦农艺性状的效应.结果显示:(1)参试的124份小麦品种(系)中23份含有Rht-B1b,7份含有Rht-D1b,22份含有Rht8基因,34份同时含有Rht-B1b和Rht8,16份同时含有Rht-D1b和Rht8,可分为6组.(2)Rht-B1b和Rht-D1b在降低株高的同时也缩短了旗叶的长度和苗期叶长,Rht8对株高的影响较弱,对旗叶和苗期叶长的影响也较小;3个矮秆基因对苗期根系长度、小穗数没有显著影响;Rht-D1b和Rht8显著增加穗粒数.研究表明,矮秆基因Rht8对小麦株高以及其他农艺性状的影响均较小,但能够显著增加穗粒数,是小麦矮化育种中比较理想的矮秆基因.

Effects of Dwarfing Genes on Some Agronomic Characteristics of Wheat

To investigate the effects of dwarfing genes Rht-B1b,Rht-D1b and Rht8 on agronomic traits of wheat,we use molecular markers analysis combined with pedigree information,124 wheat cultivars widely used in Chinese major wheat production regions were classified into different categories based on the dwarf genes carried,then the effects of dwarf genes on plant height,length of flag leaf,spikes per individual and kernels per spike were analyzed based on these data from the field and root length data from the lab.Results indicated that(1)The screening of 124 varieties with molecular markers revealed that there were 23 genotypes with dwarfing gene Rht-B1b,7 genotypes with dwarfing gene Rht-D1b and 22 genotypes with dwarfing gene Rht8,and 34 genotypes with two dwarfing genes of Rht-B1b and Rht8,and 16 genotypes with two dwarfing genes of Rht-D1b and Rht8.(2)The effects of dwarfing genes Rht-B1b,Rht-D1b and Rht8 on agronomic traits of wheat showed that the strongest effect on reducing plant height was observed for dwarf genes Rht-D1b and Rht-B1b,and then Rht8,and no significant differences was observed in seedling root length;The length of flag leaf of wheat cultivars with Rht8 was significantly longer than that of other dwarfing genes;there were no significant differences observed in spikes per individual;the kernels number per spike of wheat cultivars with dwarfing genes Rht-D1b and Rht8 were significantly higher than that with dwarf gene Rht-B1b.To summarize,the dwarfing genes Rht-B1b and Rht-D1b shorten the flag leaf length largely while reducing plant height,the dwarfing gene Rht8 had much less negative effects on other agronomic traits and also could reduce plant height to some extent,meanwhile increasing grain number per spike.Rht8 is an ideal dwarfing gene for wheat improvement.